1. Field of the Invention
This invention relates to improvement in attitude control systems for space vehicles, and more particularly, to a solid propellant attitude control system for post boost space vehicles.
2. Description of the Prior Art
In the prior art attitude control systems for affecting the various motions of post boost space vehicles, as is disclosed, for example, in U.S. Pat. No. 3,231,223 issued to C. E. Upper on Jan. 25, 1966, in U.S. Pat. No. 3,826,087 issued to Allan J. McDonald on July 30, 1974, and in application for U.S. Patent bearing Ser. No. 642,469, filed on Aug. 20, 1984 by Allan J. McDonald, the practice is to direct gas generated by a gas generator to fixed nozzles without first extracting surplus energy from the gas stream. Fixed nozzles, typically called thrusters, or fixed rocket engines are utilized for providing orientation forces in post boost vehicles. Multiple individual thrusters or rocket engines are needed to obtain the various pitch, yaw, roll, translational and axial motions desired. The use of fixed nozzles requires many nozzles to achieve maximum moment arm lengths for torque forces on the post boost vehicle. If fewer nozzles are used, higher thrust nozzles are needed in order to obtain the required thrust forces. As a result, the prior art solid propellant attitude control systems leave much to be desired from the standpoint of being energy efficient.
There is, accordingly, a need and a demand for an energy efficient solid propellant attitude control system for post boost space vehicles.